Trocar systems have been developed over the years for various endoscopic applications in the field of medicine. These trocar systems conventionally include a cannula through which a trocar or obturator or other endoscopic related tool extends. The trocar can be shielded or unshielded. Examples of shielded trocars can be seen in U.S. Pat. No. 4,654,030 by Moll et al. titled “Trocar,” U.S. Pat. No. 4,931,042 by Holmes et al. titled “Trocar Assembly With Improved Latch,” U.S. Pat. No. 4,902,280 by Lander titled “Trocar,” and U.S. Pat. No. 5,030,206 by Lander titled “Trocar.” Other shielded trocars which are more cost effective to manufacture, less bulky to handle and ship, and yet produce reliable performance, however, are still needed.
It is also known to use one or more valves positioned within or connected to a proximal end of the cannula of a trocar system. Examples of such trocar systems having one or more valves in the cannula thereof can be seen in U.S. Pat. No. 5,226,891 by Bushatz et al. titled “Seal Protection Apparatus,” U.S. Pat. No. 5,308,336 by Hart et al. titled “Seal Protection Mechanism,” U.S. Pat. No. 5,385,553 by Hart et al. titled “Trocar With Floating Septum Seal,” U.S. Pat. No. 5,782,812 by Hart et al. titled “Seal Assembly For Access Device,” U.S. Pat. No. 5,443,452 by Hart et al. titled “Seal Assembly For Access Device,” and U.S. Pat. No. 5,209,737 by Ritchart et al. titled “Lever Actuated Septum Seal.”
These devices, however, often have complex mechanical valves which can be difficult and expensive to manufacture. Accordingly, after use in surgical procedures, e.g., endoscopic, the cannulas having the valves therein are often thrown away, especially if they are not sterilizable. Therefore, this expensive cost is often past on to insurance providers and patients whom upon whom they are used.
Others of these valves for cannulas of trocar systems do not have complex mechanical valves, but can still be expensive or more difficult to manufacture. As costs often rise in the health care industry, insurance, consumers, and governmental agencies often strive to drive prices for medical devices down. Also, these other valves are often not flexible for various uses by physicians or medical personnel during surgical procedures and often can be damaged. Accordingly, there is also still a need for alternative cannula and valve configurations for trocar systems, a need less expensive trocar systems, a need for more flexible trocar systems which enhance handling thereof by medical personnel users, i.e., physicians, and trocar systems which are still effective for various endoscopic surgical procedures.